The talk concerns recent advances in the mathematical-analytical theory of semiflexible branched structures[1]. Nowadays one can model semiflexible tree-like polymers, in which the branching points may have arbitrary functionality and stiffness[2,3]. Moreover, the method allows one to treat regular hyperbranched structures in a semi-analytic way[4]. A further step forward is devoted to the investigation of semiflexible polymers containing loops, i.e. obeying closure conditions. The treatment of such objects is rendered possible through the maximum entropy principle[5], as we have shown for rings[6].